When to start treatment

BHIVA guidelines recommend that, unless enrolled in a prospective clinical trial, treatment during primary infection should only be considered for those with:[ix ]

• Neurological involvement.
• Any AIDS-defining illness.
• CD4 count persistently below 200 cells/mm³ (i.e. for three months or more).

The rationale for treatment with antiretroviral drugs (ARVs) during primary infection is to preserve specific anti-HIV immune responses, reduce morbidity associated with high viraemia and CD4 depletion, and reduce onward transmission of HIV. However, past studies have evidenced conflicting results from using early therapy, so a firm recommendation on treatment during primary infection will be made when initial results from the Medical Research Council (MRC) international study known as SPARTAC (Short Pulse Anti-Retroviral Therapy At sero-Conversion) become available (anticipated in July 2011).  

The BHIVA 2008 guidelines recommend initiating antiretroviral treatment in all patients with a CD4 cell count of less than 350 cells/mm³ (confirmed on at least one sample, absent any obvious reason for temporary CD4 depletion).

As adherence to ARV therapy is critical to successful treatment, discussion of the merits and disadvantages to ARV treatment should begin early on (such as when the CD4 count falls below 500 cells/mm³). Table 1 of the BHIVA guidelines provides an estimate of the absolute six-month risk of disease progression if HAART is initiated or deferred, broken down according to age, CD4 cell count, and viral load.

For individuals whose CD4 count is equal to or over 350 cells/mm³, ARV treatment should be started or considered in the following circumstances:

• A diagnosis of AIDS or any HIV-related co-morbidity.

• Hepatitis B infection, where treatment of HBV is indicated.

• Hepatitis C infection, where treatment of HCV is deferred.

• A CD4 percentage of less than 14%.

• Established cardiovascular disease or a risk of it (i.e. >20% over ten years).

The writing group notes that treatment at this stage might also be considered in discordant couples (as an adjunct to safer sex). Patients who present with lymphoma and who are starting chemotherapy should also start ARV therapy, regardless of CD4 cell count.

ARV treatment should also be considered in someone with an opportunistic infection (OI) and would ideally start early (a median of twelve days after treatment for the opportunistic infection starts and after results from resistance and HLA-B*5701 testing become available).